A conventional electromagnetic relay includes a casing having a housing space open to an external through an opening, and a base attached to the casing to close the opening. The housing space communicates with the external through a vent hole formed on the base.
The base has a terminal insertion hole into which a terminal is inserted. The terminal insertion hole and the vent hole are next to each other to communicate with each other. Thus, when flame generated inside the housing space passes through the vent hole, the base and the terminal extinguish the flame by drawing heat from the flame (refer to Patent Literature 1, for example).